title: 6a-Nitro-6-phenyl-6,6a,6b,7,8,9,10,12a-octa-hydro-spiro-[chromeno[3,4-a]indol-izine-12,3'-indolin]-2'-one.
abstract: In the title compound, C28H25N3O4, the central pyrrolidine ring adopts adopts an envelope conformation with the N atom as the flap and the piperidine ring adopts a chair conformation. The pendant pyrrolidine ring is almost planar (r.m.s. deviation = 0.008 Å). An intra-molecular C-H⋯O inter-action closes an S(6) ring. In the crystal, inversion dimers linked by pairs of N-H⋯O hydrogen bonds generate R 2 (2)(8) loops.
authors.affiliation: Centre of Advanced Study in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai 600 025, India.
authors.forename: Seenivasan Karthiga
authors.initials: SK
authors.lastname: Devi
authors.forename: Thothadri
authors.initials: T
authors.lastname: Srinivasan
authors.forename: Jonnalagadda Naga Siva
authors.initials: JN
authors.lastname: Rao
authors.forename: Raghavachary
authors.initials: R
authors.lastname: Raghunathan
authors.forename: Devadasan
authors.initials: D
authors.lastname: Velmurugan